Flicker noise is a type of electronic noise present in electronic devices operating using direct current (DC). Flicker noise is a result of impurities in a channel of a device or variations in charge generation or elimination in a device, in some instances. Flicker noise is a change in resistance of the device and manifests as a change in voltage or current based on Ohm's Law.
Electronic noise impacts reliability of a device because as an amount of noise increases, accurately determining an output of the device becomes more difficult. In high-frequency devices, flicker noise contributes a minor portion of an overall noise of the device because an amount of white noise dominates the amount of flicker noise. In low-frequency devices, the overall noise is reduced to a noise inherent in the device, i.e., phase noise. In a transition area between high-frequency devices and low-frequency devices, flicker noise is determined as being a significant factor in determining the overall noise of the device. As technology nodes shrink, a frequency of the transition area for overall noise of a device increases.
In some instances, the flicker noise is measured using external equipment. In some instances, the flicker noise is extrapolated based on simulated noise as an operating frequency of a device is altered.